Somewhere along the line, the camera point for the 2D views there got set to the special numeric value for Infinity...

There is definitely a bug in there somewhere, but unfortunately the real bug is in the thing that set the camera to that invalid value at some point previously.

I have added in some new safeguards for the next beta to avoid setting the camera to an invalid value like this, so that should help to avoid this in the future. If you can get it to happen again, please let me know and especially if you can save off the model in its state before this happens and then tell me how to repeat it, that would help to zero in on the actual bug. But it may be difficult to run across it again.

In the meantime the procedure that Danny wrote above (hide everything by Ctrl+A and then Edit/Hide, and then push View/Reset All) - will reset the camera locations of all the viewports to their initial default positions and that removes the invalid camera value and should let you work normally after that.

I drew two concentric circles(was going to create a tube), selected both then tried to extrude them. Nothing happened and I tried again. Same thing.
I think that's when I noticed the top and left windows were blank.

As you suggested I tried to repeat these actions but everything worked as it should.